Jolla1 updated without hitch
Jolla Tablet updated without a hitch
Jollafied Intex Auqa Fish only worked from shell

Intex Aquafish shows now another update of around 1MB but i can not update it cause Phone suddenly tells me System Data only had 471 MB free.

Noob question: What is safe to delete? Where are the updates stored?

As normal user i do not know what all the fuss for Sailfish3 big update is about.